Vent cowl



April 30, 1963 g 3,087,409-

VENT COWL Filed Dec. 3, 1959 mmvrokx E John H. Carr Mmber of me firm..

BY ECKHOFF suclmfi s.

United States Patent 3,087,409 VENT COWL John H. Carr, Mountain View, Caiif, assignor to Dura- Vent Corporation, a corporation of Delaware Filed Dec. 3, 1959, Ser. No. 857,098 2 Claims. (Cl. 98-84) This invention relates to a vent cowl structure and more particularly relates to a metal structure of welded or riveted construction.

Vent cowls or caps are commonly used with vents for exhausting combustion gases, such as from space heaters or water heaters and it is highly desirable that such cowls present a minimum back pressure to the flow of gases therefrom. It is also desirable that such structures function regardless of wind direction and particularly that the cowl not act as an air scoop under any wind conditions whereby -a down draft would be produced. Further, such vent cowls should be effective in excluding rain or other foreign matter from entering the vent, as well as preventing access by birds or small animals.

It is an object of the present invention to provide a vent cowl structure of simple design but which has all of the above desirable features and which is inexpensive to construct and which is very durable.

In the drawings forming part of this application:

FIGURE 1 is a perspective view, partially in section, of a vent cowl embodying the present invention.

FIGURE 2 is an elevational view of a vent cap of FIGURE 1, partly in section.

FIGURE 3 is a perspective view of one of the brackets used to support the deflector and top cap to the base.

Referring now to the drawings by reference characters, there is shown a base or coupling section 5 which may have a top rolled over edge 7 and a bottom rolled over edge 9. The base section 5 preferably has an indentation 11 therein so that the bottom portion of the base pipe is slightly smaller than the top. The base section 5 also preferably has a series of indentations 13, preferably four in number, which may be used for securing the base section to a vent pipe. Fastened to the base section 5 adjacent the top thereof are a series of brackets, preferably three in number, generally designated 15. Each of the brackets 15 has a flat center section 17 with an inner flange 19 and an outer flange 21 integral therewith. It will be noted that the flanges 19 and 21 are turned in opposite directions. The inner flange 19 has holes 20 therein for attachment of the flange to the base, while the flange 21 has holes 22 for attachment of the deflector and hole 26 for attachment of the top cap. The inner lange 19 is relatively short while the outer flange 21 is relatively long. The bracket 15 has a flat base 23 while the tops of the flanges 19 and 21 are joined with the angling edge 25.

Deflector 27 is provided which is mounted concentric to the base member 5 in such a relationship that its top extends somewhat above the top of the base member 5. The deflector preferably has two reinforcing beads 29 for greater strength. The deflector 27 is substantially larger than the base pipe 5 and preferably has a net cross-sectional area (the actual cross-sectional area of the outer deflector minus the cross-sectional area of the base pipe) at least equal to and preferably on the order of twice as large as that of the base pipe. It has been found that this relationship is essential to prevent back pressure.

A top cap 31 is provided having an outside diameter substantially greater than that of the deflector. The cap 31 has a central dome portion 33 which extends to an annular trunk 35. The inner wall of the annular trunk 35 is of substantially the same diameter and concentric "ice with the deflector. Extending beyond the annular trunk 35 is the outer rim 37.

Preferably, the vent cowl is assembled by riveting although other suitable means, such as spot welding, may be employed. The holes 20 in the flange 19 provide a convenient place for riveting the bracket to the base member 5 and the holes 22 are used to fasten the deflector 27 to the bracket. The hole 26 is used for fastening the top cap to the bracket.

It is believed apparent from the foregoing that I have provided an inexpensive yet effective vent cap for use in connection with venting gases to the atmosphere.

I claim:

1. A vent cowl comprising:

(a) an open-ended met-a1 cylinder having means thereon for securing said cylinder to an upstanding pipe whereby to permit said cylinder to serve as an extension thereof;

(b) at least two brackets secured to the exterior of said metal cylinder, said brackets each consisting of a flat sheet of metal having two straight parallel edges and having two opposed straight edges not parallel with one another whereby the two parallel edges are of unequal length;

(0) a flange integral with each of said parallel edges and at a right angle relative to the said sheet of metal at the point of attachment thereto, said brackets 'being secured to said metal cylinder along a longitudinal surface thereof by rivets through each of the flanges integral with the shorter bracket edge;

(d) a second open-ended metal cylinder, said second cylinder being of a diameter in excess of the diameter of said first cylinder;

(e) means securing the said second cylinder concentrically about the upper portion of said first cylinder to said flanges integral with the longer edges of said brackets, said second cylinder being so mounted that a portion of each bracket and flange integral with said longer edge extends thereabove and a portion of said second cylinder extends above the uppermost edge of said first cylinder while a larger portion thereof extends below the uppermost edge of said first cylinder;

(7) a top cap of a generally dish-shaped configuration and of larger diameter than said second cylinder, said top cap having a vertical annular trunk in an area spaced from the outermost edge thereof, said trunk being of substantially the same diameter as said second cylinder;

(g) and means securing said top cap at the vertical annular trunk thereof to the said portions of said flanges of said brackets extending above said second cylinder whereby said top cap is positioned over the said second cylinder with sufiicient space between the lowermost surface of the said top cap and the uppermost edges of said second cylinder to permit gas to pas-s therebetween.

2. The vent cowl of claim 1 wherein the cross-sectional area of the said second cylinder is at least twice the crosssectional area of the said first cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 2,068,916 Heppenstall Jan. 26, 1937 2,739,520 Cur-ran Mar. 27, 1956 2,753,786 White July 10, 1956 FOREIGN PATENTS 24,468 Great Britain 1907 935,323 France June 16, 1948 509,107 Belgium Feb. 9, 1952 

1. A VENT COWL COMPRISING: (A) AN OPEN-ENDED METAL CYLINDER HAVING MEANS THEREON FOR SECURING SAID CYLINDER TO AN UPSTANDING PIPE WHEREBY TO PERMIT SAID CYLINDER TO SERVE AS AN EXTENSION THEREOF; (B) AT LEAST TWO BRACKETS SECURED TO THE EXTERIOR OF SAID METAL CYLINDER, SAID BRACKETS EACH CONSISTING OF A FLAT SHEET OF METAL HAVING TWO STRAIGHT PARALLEL EDGES AND HAVING TWO OPPOSED STRAIGHT EDGES NOT PARALLEL WITH ONE ANOTHER WHEREBY THE TWO PARALLEL EDGES ARE OF UNEQUAL LENGTH; (C) A FLANGE INTEGRAL WITH EACH OF SAID PARALLEL EDGES AND AT A RIGHT ANGLE RELATIVE TO THE SAID SHEET OF METAL AT THE POINT OF ATTACHMENT THERETO, SAID BRACKETS BEING SECURED TO SAID METAL CYLINDER ALONG A LONGITUDINAL SURFACE THEREOF BY RIVETS THROUGH EACH OF THE FLANGES INTEGRAL WITH THE SHORTER BRACKET EDGE; (D) A SECOND OPEN-ENDED METAL CYLINDER, SAID SECOND CYLINDER BEING OF A DIAMETER IN EXCESS OF THE DIAMETER OF SAID FIRST CYLINDER; (E) MEANS SECURING THE SAID SECOND CYLINDER CONCENTRICALLY ABOUT THE UPPER PORTION OF SAID FIRST CYLINDER TO SAID FLANGES INTEGRAL WITH THE LONGER EDGES OF SAID BRACKETS, SAID SECOND CYLINDER BEING SO MOUNTED THAT A PORTION OF EACH BRACKET AND FLANGE INTEGRAL WITH SAID LONGER EDGE EXTENDS THEREABOVE AND A PORTION OF SAID SECOND CYLINDER EXTENDS ABOVE THE UPPERMOST EDGE OF SAID FIRST CYLINDER WHILE A LARGER PORTION THEREOF EXTENDS BELOW THE UPPERMOST EDGE OF SAID FIRST CYLINDER; (F) A TOP CAP OF A GENERALLY DISH-SHAPED CONFIGURATION AND OF LARGER DIAMETER THAN SAID SECOND CYLINDER, SAID TOP CAP HAVING A VERTICAL ANNULAR TRUNK IN AN AREA SPACED FROM THE OUTERMOST EDGE THEREOF, SAID TRUNK BEING OF SUBSTANTIALLY THE SAME DIAMETER AS SAID SECOND CYLINDER; (G) AND MEANS SECURING SAID TOP CAP AT THE VERTICAL ANNULAR TRUNK THEREOF TO SAID PORTIONS OF SAID FLANGES OF SAID BRACKETS EXTENDING ABOVE SAID SECOND CYLINDER WHEREBY SAID TOP CAP IS POSITIONED OVER THE SAID SECOND CYLINDER WITH SUFFICIENT SPACE BETWEEN THE LOWERMOST SURFACE OF THE SAID TOP CAP AND THE UPPERMOST EDGES OF SAID SECOND CYLINDER TO PERMIT GAS TO PASS THEREBETWEEN. 